The present invention is related to a hot/cold water inlet and outlet structure for a ceramic core shaft of a single handled faucet, comprising a valve housing, a switch valve set, a valve mount, an upper switch valve, a lower switch valve, and a sealing ring wherein the valve housing has a valve chamber disposed at the interior thereof for the switch valve set and the valve mount thereof to be adapted therein respectively. The upper switch valve has a regulating recess defined at the bottom thereof; the lower switch valve includes a pair of arc hot/cold water inlet holes and a water outlet hole with indented groove seats defined thereon, correspondingly matched to arc hot/cold water inlet passages and a water outlet passage with higher protruded walls of the valve mount thereof; whereby, the lower switch valve is overlapped on top of the valve mount with the indented groove seats thereof securely joined to the higher protruded walls thereof in sealing engagement, further pressing downwards the sealing ring adapted at the valve mount therein to effectively prevent water leakage in use and ensure the precise engagement of the lower switch valve with the valve mount thereof
Please refer to FIGS. 1, 2. A conventional ceramic core shaft of a single handled faucet is mainly made up of a valve housing 10, a switch valve set 20, a valve mount 30, an upper switch valve 31, a lower switch valve 32, and a sealing ring 33. The valve housing 10 has a valve chamber 11 disposed at the interior thereof for the switch valve set 20 and the base mount 30 to be adapted therein. The switch valve set 20 is equipped with a control stick seat 21 with a turning protruded block 211 disposed at the upper section thereof, and a support seat 22 with a turning cut area 221 and a switch valve 23 disposed at the lower section sequentially correspondingly matched to the valve mount 30 thereof. The upper switch valve 31 has a regulating recess 311 defined at the bottom thereof, and the lower switch valve 32 is provided with a flat bottom with a pair of arc hot/cold water inlet holes 321, 322 and a water outlet hole 323 disposed thereon, correspondingly matched to arc hot/cold water inlet passages 301, 302 and a water outlet passage 303 of the valve mount 30 thereof. The arc hot/cold water inlet passages 301, 302 and the water outlet passage 303 thereof are defined by protruded rib walls 3011, 3021, 3031, each extending upwards at the periphery thereof respectively, which are further circumscribed by a stop wall 304 of the same height at the outside thereof with a channel groove 305 formed therein for the sealing ring 33 to be adapted thereto and abutted against the lower switch valve 32 thereof.
There are some drawbacks to such conventional ceramic core shaft of a single handled faucet. Most of all, the protruded rib walls 3011, 3021, 3031 and the stop wall 304 thereof, designed in the same height, makes the valve mount 30 only abut against the flat bottom of the lower switch valve 32 when overlapped thereon in assembly and the sealing ring 33 simply adapt at the valve mount 30 therein without precise engagement, which may reduce the function of the sealing ring 33 and cause the leakage of water in use.